Lack of good response to Milk ingestion has been noted in gallbladder diseases. No regression relationship has been established between Gallbladder Emptying Rate (GBER) and Gallbladder Volume (GBV). To investigate 20th minute GBER in adult Africans of Nigerian descent. Fifty healthy volunteers (29 men and 21 women) underwent serial Ultrasound scanning of the gallbladder between January to March 2005. The length, width and height measurements of the gallbladder were taken with 3.5MHz linear phase array tranducer in preprandial (Fasting) state and 20 minutes post-prandial phase. Gallbladder volumes were calculated and the 20th minute emptying rate computed. Anthropometric variables were equally measured. GBER was correlated with other clinical parameters. The mean GBER in men ± standard deviation was 0.842 ± 0.47 and 0.721 ± 0.512 in women. There was no significant difference between mean GBER of men and women (P>0.05). The calculated GBER showed strong and significant correlation with GBV in men (r= 0.8427; p